Doesn't look as bad as what I'd thought reading the text! Let's make this simple, first off, count a 45º fitting as ½ of a 90ºelbow. It takes 2-45º fittings to equal 1 90º elbow. The one mistake I see from the pics is that the second transition is in a horizontal section of pipe; that leads to a trap for condensate, which in effect reduces your inside diameter of the 2" pipe. NOT GOOD! Rules for transitions: (a)must be located outside of furnace cabinet;(b)must be installed in verticle sections of pipe.
last observation: why in the world did they start out with 2" to 3" back to 2"???? that's crazy!
It looks to me that all fittings are of the long radius type, which is a good thing.